Microcystic Adnexal Carcinoma with Xanthomatous Reaction

Society for Publication of Acta Dermato-Venereologica Microcystic adnexal carcinoma (MAC) commonly mani­ fests as a solitary plaque located on the face, including the upper or lower lips (1). This neoplasm is locally aggressive with deep infiltration and is characterized by frequent recurrence. Pathologically, MAC displays both eccrine and follicular differentiation, and is thought to originate from pluripotent adnexal keratinocytes. The superficial lesion is composed of numerous keratinous cysts, and small islands or cords of basaloid and squa­ mous epithelium with ductal differentiation. The deeper part of the tumour consists of small nests and strands of cells. Those components are surrounded by a dense collagenous stroma (2).